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Welcome to Wikipedia's Energy portal, your gateway to energy. This portal is aimed at giving you access to all energy related topics in all of its forms.
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A plasma globe, using electrical energy to create plasma, light, heat, movement and a faint sound

In physics, energy (from Ancient Greek ἐνέργεια (enérgeia) 'activity') is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat and light. Energy is a conserved quantity—the law of conservation of energy states that energy can be converted in form, but not created or destroyed. The unit of measurement for energy in the International System of Units (SI) is the joule (J).

Common forms of energy include the kinetic energy of a moving object, the potential energy stored by an object (for instance due to its position in a field), the elastic energy stored in a solid object, chemical energy associated with chemical reactions, the radiant energy carried by electromagnetic radiation, and the internal energy contained within a thermodynamic system. All living organisms constantly take in and release energy.

Due to mass–energy equivalence, any object that has mass when stationary (called rest mass) also has an equivalent amount of energy whose form is called rest energy, and any additional energy (of any form) acquired by the object above that rest energy will increase the object's total mass just as it increases its total energy.

Human civilization requires energy to function, which it gets from energy resources such as fossil fuels, nuclear fuel, or renewable energy. The Earth's climate and ecosystems processes are driven by the energy the planet receives from the Sun (although a small amount is also contributed by geothermal energy). (Full article...)

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Stella North (left) and South (right) power stations
Viewed from Newburn Bridge on 31 October 1987

The Stella power stations were a pair of now-demolished coal-fired power stations in the North East of England that were a landmark in the Tyne valley for over 40 years. The stations stood on either side of a bend of the River Tyne: Stella South power station, the larger, near Blaydon in Gateshead, and Stella North power station near Lemington in Newcastle. Their name originated from the nearby Stella Hall, a manor house close to Stella South that by the time of their construction had been demolished and replaced by a housing estate. They operated from shortly after the nationalisation of the British electrical supply industry until two years after the Electricity Act of 1989, when the industry passed into the private sector.

These sister stations were of similar design and were built, opened, and closed together. Stella South, with a generating capacity of 300 megawatts (MW), was built on the site of the Blaydon Races, and Stella North, with a capacity of 240 MW, on that of the former Lemington Hall. They powered local homes and the many heavy industries of Tyne and Wear, Northumberland and County Durham. The large buildings, chimneys and cooling towers were visible from afar. Their operation required coal trains on both sides of the river to supply them with fuel and river traffic by flat iron barges to dump ash in the North Sea. After their closure in 1991, they were demolished in stages between 1992 and 1997. Following the stations' demolition, the sites underwent redevelopment: the North site into a large business and industrial park, the South into a housing estate. (Full article...)

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Photo credit: NASA/TRACE
Plasma being channeled by the magnetic field loops of a sunspot.

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The Geysers
The Geysers

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James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish mathematician and theoretical physicist. His most significant achievement was formulating a set of equations – eponymously named Maxwell's equations – that for the first time expressed the basic laws of electricity and magnetism in a unified fashion. Maxwell's contributions to physics are considered by many to be of the same magnitude as those of Isaac Newton and Albert Einstein.

Maxwell studied natural philosophy, moral philosophy, and mental philosophy at the University of Edinburgh, before graduating in mathematics at the University of Cambridge, where he would conduct much of his career. He built on Michael Faraday's work on magnetic induction, using elements of geometry and algebra to demonstrate that electric and magnetic fields travel through space, in the form of waves, and at the constant speed of light. Finally, in 1861, Maxwell proposed that light consisted of undulations in the same medium that is the cause of electric and magnetic phenomena. In the same year he was elected to the Royal Society.

In 1864, Maxwell presented what are now known as Maxwell's equations to the Royal Society. These collectively describe the behaviour of both the electric and magnetic fields, as well as their interactions with matter.

In the news

7 April 2024 – Russian invasion of Ukraine
The IAEA reports that the Zaporizhzhia Nuclear Power Plant's Unit 6 was targeted by a drone strike, although nuclear safety has not been compromised, according to the statement. (IAEA)
4 April 2024 –
Researchers at the Dark Energy Spectroscopic Instrument in Arizona, United States, release the largest 3D map of the universe featuring more than six million galaxies. Using this map, researchers are able to measure the acceleration of the expansion rate of the universe with unprecedented accuracy, detecting hints that the rate of expansion has been increasing over time. (The Guardian) (Berkeley Lab)

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